ANU Squirrel Glider Research Studies

The South West Slopes (SWS) Restoration Study was established in 2000 to examine how different faunal groups such as birds, possums and reptiles respond to tree plantings and remnant vegetation on farms. The project area is located in the SWS bioregion, southern New South Wales and spans an area from Howlong in the south to Junee in the north.

Below are the abstracts and links to the Australian National University’s Publications on squirrel gliders, from the SWS Restoration Study.

The characteristics of den trees used by the squirrel glider

We measured 146 den trees used by the squirrel glider and compared the data with random trees to quantify the key characteristics of den sites. The likelihood of use as a den tree increased with increasing numbers of visible tree hollows and tree size. Dieback was also a positive indicator of den use. However, when visible hollows within a tree are abundant, dieback-free trees were preferred. Measures of den tree context such as basal area, the number of neighbouring large trees and distance to the next nearest tree, were also found to be important determinants of the likelihood of usage. The above variables were combined into a multiple regression model. The squirrel glider favoured particular Eucalyptus species and some broader eucalypt groups. We believe such variations were most likely due to interspecific differences in hollow development and dieback among the various groups, rather than bark type, a factor previously cited as an important determinant of den tree usage. The ‘best’ model had high negative predictive power, suggesting it would be useful for identifying (1) trees that could be felled without a loss of this critical habitat resource (e.g. at development sites) and (2) areas unsuitable for potential squirrel glider relocation or habitat enhancement. Squirrel gliders show preference for a combination of tree and tree context features in selecting den trees. Understanding these features will help managers enhance and protect denning resources for this species. Read more…

The use of den trees by the squirrel glider

We examined the use of tree hollows by the squirrel glider. Over a five-month study, individual squirrel gliders used multiple hollow trees (average = 7) as den sites. Den sites were often adjacent to areas where nocturnal activities took place. The average distance between den sites used by individual gliders on successive days was 218 m. Dens were often shared by an adult pair and a juvenile. Den trees were disproportionably used, with gliders showing preference for 1–2 primary den trees often located on steep slopes. Our findings have implications for the number and spatial arrangement of den trees needed to promote the conservation of populations of the squirrel glider, particularly where land is used for agriculture and livestock grazing. Read more…